It is common to have mild pain after a root canal procedure. But persistent pain after root canal can be an indication of complications. Few common causes are irritation of periodontal tissues, formation of periapical abscess, failed root canal or formation of a sterile abscess. Improper cleaning of root canal, infected tissue left inside the tooth, improper filling and sealing of root canal are few possibilities. If the pain is severe visit your dentist and get examined. Treatment will be specific based on the cause. Do write to me again with more queries.
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